This is a tricky one because both “learn” and “learn about/of” refer to gaining new knowledge/information, but let’s take a look at the differences. First, the definitions (from the Cambridge online dictionary):

to learn: to get new knowledge or skill in a subject or activity

to learn about/of: to hear facts or information that you did not know

So, when is it appropriate to use each one?

First, you can “learn” subjects, including languages, as in “I learned a little French when I was younger.”

You can also “learn” how to do things, as in “I recently learned how to use ChatGPT.” The word “how” can be left out if you wish. So, for example, you can say either “I learned how to swim when I was 6” or “I learned to swim when I was 6.”

When we “learn” something, we gain a skill, the ability to do something, such as speaking French, using ChatGPT, or swimming.

However, when we simply acquire new information which is not necessarily related to a skill or the ability to do something, we “learn about/of” it. 

I “learned” French in school, but I did not “learn” the French Revolution. I “learned about” it. I was taught the details, like dates and names. 

If you read an article about who developed ChatGPT, you are not learning how to use it. You are not acquiring a skill. You are “learning about” it, gaining new information about it.

Finally, what about using “about” or “of” - is there a difference? While dictionaries may give the same definition for both, they are used in slightly different contexts. 

Typically, we use “learn of” when we first become aware of something but don’t have much knowledge or many details. For example…

Recently, I “learned of” a kind of insect called a “no-see-um” from my grandmother. I became aware of this insect’s existence, but I didn’t know anything about it. Later, I looked up no-see-ums online to “learn about” them, to get the details. As I read more, I also “learned” how to get rid of them. 

So, when I “learned of” them, I became aware of them. When I “learned about” them, I got information/details about them (their size, habitat, food, etc.). When I “learned” how to get rid of them, I acquired a skill (knowledge that allows me to actually take action).

As I said at the beginning, it’s tricky, but I hope these examples have helped a little to explain the subtle nuances!